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Chapter 5 4th Edition Learning Copyright 2004 Prentice Hall 5-1 What is Learning? • Learning occurs when experience produces a relatively permanent change in behavior. Copyright 2004 Prentice Hall 5-2 Classical Conditioning • Classical conditioning involves pairing an unconditioned stimulus (UCS), which automatically elicits an unconditioned response (UCR), with a conditioned stimulus (CS), which is neutral at the start of conditioning. • Several pairings during an acquisition phase lead to a situation in which the CS presented by itself elicits a conditioned response (CR). Copyright 2004 Prentice Hall 5-3 Classical Conditioning • Several pairings during an acquisition phase lead to a situation in which the CS presented by itself elicits a conditioned response (CR). Copyright 2004 Prentice Hall 5-4 Classical Conditioning • The classically conditioned response is eliminated or extinguished when the UCS is removed or not presented; this process is called extinction. Copyright 2004 Prentice Hall 5-5 Classical Conditioning • Spontaneous recovery of the CR occurs when time is allowed to pass between extinction sessions. Copyright 2004 Prentice Hall 5-6 Classical Conditioning • Generalization occurs when CRs are elicited by stimuli that are similar to the CS. • Discrimination is the opposing process; it involves responding only to the appropriate CS. Copyright 2004 Prentice Hall 5-7 Classical Conditioning • John Watson and Rosalie Rayner demonstrated that emotions can be learned by classically conditioning 9-month-old Little Albert to fear a white rat. Copyright 2004 Prentice Hall 5-8 Classical Conditioning • This child exhibited a phobia, which is a fear for certain activities, objects, or situations. • The research conducted by Watson and Rayner would not be considered ethical by present-day standards. Copyright 2004 Prentice Hall 5-9 Classical Conditioning • Our understanding of classical conditioning has been subject to revision since Pavlov introduced the basic processes. • For example, although the association of CS with UCS is important in establishing conditioning, the real key is the degree to which the CS predicts occurrence of the UCS. • Previous trials of a CS-UCS pairing can serve to block the effectiveness of a second CS. Copyright 2004 Prentice Hall 5-10 Classical Conditioning • Previous trials of a CS-UCS pairing can serve to block the effectiveness of a second CS. Copyright 2004 Prentice Hall 5-11 Classical Conditioning • For many species, the pairing of a novel taste with the experience of illness results in learning an aversion to that taste. Copyright 2004 Prentice Hall 5-12 Classical Conditioning • Taste-aversion learning occurs readily in humans; birds, however, more readily associate a color with illness. • Preparedness is evident when some species are more likely to form certain associations than others. Copyright 2004 Prentice Hall 5-13 Operant Conditioning • Operant conditioning occurs when an organism performs a target response that is followed by a reinforcer, which increases the probability that the behavior (target response) will occur again. Copyright 2004 Prentice Hall 5-14 Operant Conditioning • All reinforcers increase the frequency of the response they follow. • Positive reinforcers are presented after the target response has been made; negative reinforcers are withdrawn or taken away after the target response has been made. Copyright 2004 Prentice Hall 5-15 Operant Conditioning Copyright 2004 Prentice Hall 5-16 Operant Conditioning • Primary reinforcers (for example, food) satisfy basic biological needs; secondary (conditioned) reinforcers (for example, money) acquire their power to reinforce behavior by being associated with primary reinforcers. Copyright 2004 Prentice Hall 5-17 Operant Conditioning • Complex responses may be acquired gradually through the process of shaping (successive approximations). • Psychologists can keep track of the rate of responding by using a cumulative record, which keeps track of all target responses made by an organism across time. Copyright 2004 Prentice Hall 5-18 Operant Conditioning • Once a behavior has been acquired, it may be reinforced according to a particular schedule of reinforcement. • When a ratio schedule is in effect, the number of responses is important. Copyright 2004 Prentice Hall 5-19 Operant Conditioning • Fixed-ratio (FR) schedules require that a set number of responses be made before a reinforcer is delivered. • Variable-ratio (VR) schedules require that the participant perform differing numbers of responses to obtain a reinforcer. • With an Interval schedule, a certain amount of time must pass before a response is reinforced. Operant Conditioning • With a fixed-interval (FI) schedule, the time interval is constant. • The time interval changes after each reinforcer is delivered when a variable-interval (VI) schedule is used. • Ratio schedules generally produce higher rates of responding than interval schedules. Copyright 2004 Prentice Hall 5-21 Operant Conditioning • Operant responses that are not reinforced each time during training take much longer to extinguish than ones that have received continuous reinforcement. • This phenomenon is known as the partial (intermittent) reinforcement effect. Copyright 2004 Prentice Hall 5-22 Operant Conditioning • A discriminative stimulus signals that responses will be reinforced. • Behavior is said to be under stimulus control when responding occurs only when the discriminative stimulus is present. Copyright 2004 Prentice Hall 5-23 Operant Conditioning • The opposite of reinforcement, punishment, involves presentation or withdrawal of stimuli called punishers, which results in a suppression of the target behavior. Copyright 2004 Prentice Hall 5-24 Cognitive and Social Perspectives On Learning • Insight learning involves restructuring our perceptual stimuli to achieve the solution to a problem. • Such perceptual restructuring and solutions typically occur rapidly. Copyright 2004 Prentice Hall 5-25 Cognitive and Social Perspectives On Learning • Latent learning occurs when learning has taken place but is not demonstrated until a later time. Copyright 2004 Prentice Hall 5-26 Cognitive and Social Perspectives On Learning • Observational learning takes place when we observe and identify with the behaviors of others. • Advertisements and television commercials appeal to this process. • Televised violence may result in observational learning and lead to an increase in violent behaviors. Copyright 2004 Prentice Hall 5-27